Cost Drivers in Two-Stage Treatment of Hip Periprosthetic Joint Infection With an Antibiotic Coated Cement Hip Spacer

Background: The current gold standard for treating chronic Periprosthetic Joint Infection (PJI) is a 2-stage revision arthroplasty. There has been little investigation into what specific patient and operative factors may be able to predict higher costs of this treatment. Methods: An institutional electronic health record database was retrospectively queried for patients who developed a PJI after a total hip arthroplasty, and underwent removal of the prosthesis and implantation of an antibiotic-impregnated articulating hip cement spacer. Patient demographics, surgical variables, hospital readmissions, emergency department visits, and post-operative complications were collected. Total costs were captured through an internal accounting database through 2 years post-operatively. Negative binomial regressions were utilized for multivariable analyses. A total of 55 hips with PJI were available for cost analyses. Results: A comorbidity index score was associated with a 70% increase (Odds Ratio (OR): 1.7 [1.18-2.5], P = .003) in total costs at 2-years. Illicit drug use was associated with a 70% increase in costs at 1-year post-operatively (OR 1.7 [1.18-2.5], P = .003). Metal-on-poly liners were associated with a 22% decrease in cost at 2-years post-operatively when compared to Cement-on-Bone articulating spacers, and Metal-on -poly-constrained liners accounted for 38% lower costs at 1-year (OR 0.62 [0.44-0.87], P = .004). Use of an intraoperative extended trochanteric osteotomy was associated with a 46 and 61% increase in cost at 1-year (OR 1.46 [1.14-1.89]) and 2-years (OR 1.61 [1.26-2.07], P < .001) post-operatively. Conclusion: Age, comorbidity index score, drug use, and extended trochanteric osteotomy were associ-ated with increased costs of PJI treatment. This may be used to improve reimbursement models and target areas of cost savings. (c) 2022 Elsevier Inc. All rights reserved.